USB connection causes computer lockup

I have a Dell Dimension 4100, 1ghz, 512MB, with two USB ports on the back. I have a 4-Port powered USB hub connected to each port. One hub has a cordless mouse and keyboard plugged into it. The other one a joystick. Everything works fine until I try to plug something else into one of the hubs. It doesn't matter if it is a camera, card reader, flash drive or iPaq it locks up the computer. Sometimes it will clear itself after a few minutes. Or when it does start working, as soon as data starts transferring it locks up. It will not work at all when connecting to the iPaq. The only way to unlock it is to unplug the device. When it stops working the balloon comes up in the tray saying there has been a malfunction, click here for details. When I can click there it tells me nothing that helps.

Why does it do this? If I put a card in it would that fix it? If so, can I install a 2.0 card in this old of a system?

Thanks.

 

I don't know exactly what the problem is. However, some information about how USB works might be useful I think.

Basically USB assigns bandwidth based on the order devices are added to the bus. So the first device connected to a USB bus will get the largest chunck of bandwidth, the second device a smaller chunk of bandwidth, the third a smaller still chunk of bandwidth.

It strikes me that with the way you have configured your system, the majority of bandwidth has already been allocated before you add your extra device, and these last devices are fairly bandwidth intensive.

I would suggest that you connect the keyboard, mouse, and joystick to one USB bus/port (via one of your hubs), and use the other bus/port for connecting devices that you occasionally need to grab data from. You may need to juggle the order you connect joystick, mouse, and keyboard so as to get the optimum performance.

I'm not sure whether the system caches device bandwidth allocation. That is if you connect a device and then unplug it and then plug in a second device: whether the system remembers the first device and holds its bandwidth, thereby giving the second device less bandwidth; or it forgets the first device and sees the new device as a new first device (hope that makes sense). I suspect that there is some caching, and that it may need a reboot to clear it. I would suggest you remove all the USB devices, and then reboot the system before reconnecting them in the new arrangement.

 

Sounds like a power problem to me. As ReggieB suggests try juggling the connection order to redistribute the power requirements.

 

Thanks for the replies. Unfortunately I tried your suggestions and it didn't seem to solve the problem. I even tried switching the hubs and trying ports that were ordinarily not used. The three devices are recognized with no problem. As soon as I plug in the iPaq and the sync program starts the computer freezes. When I turn off the iPaq it recovers.

BTW, I am running XP-Home Edition and the system is 3.5 years old. The RAM, video card, hard drive and power supply have been upgraded since then.

The balloon that sometimes comes up when it freezes (I suppose it is not really a freeze, but a loss of keyboard and mouse) reads: USB Device Not Recognized. One of the USB devices attached to this computer has malfunctioned and Windows does not recognize it. For assistance (something like click here). I have a total loss of control when attempting a connection with the iPaq, but with a flash drive or camera I have sometimes been able to click "there ". It goes to a help area where it asks questions and the user selects an answer and so on. The last time I was able to do it was not helpful.

The hubs are powered. Isn’t that supposed to take some demand off the power from the computer?

Any other suggestions besides getting a new computer? Is it just that the old Dell will not handle it?

Thanks again.

 

OK, some other things to try. Delete the USB controllers in the device manager, reboot anf let XP install them again.

You are running XP SP1+ on the PC?

Check with the Motherboards web site for updated drivers pertaining to your board model.

Make sure you are running latest drivers for other hardware as well, just in case an unrelated problem is having an effect.

You have plugged the iPaq directly into one/both of the USB connectors on the M/B without connecting through a hub?

Checked for updates for the IPaq pertaining to USB connection?